1. Field of the Invention
The present invention relates to the safety measures required in the medical field to protect patients and operators from undesired radiation exposure.
2. Invention Disclosure Statement
Modern laser therapy has gained a well-accepted role in many classical parts of medical therapy methods. Nearly every procedure that employs conventional heat producing sources such as microwaves or electromagnetic field applications can also be performed using laser sources at a correct wavelength. Laser heat sources are an advantage over the prior art, because the area to be treated can be targeted specifically. The laser wavelength can be matched to the absorption wavelengths of water or hemoglobin to more accurately treat a medical problem. Suitable laser sources with sufficiently high output powers have become commercially available. Significant progress has been made in designing medical application lasers such as Q-switched Neodymium family lasers, compact carbon dioxide lasers, and in particular diode lasers.
Medical laser therapy methods are generally divided in two substantial classes: direct open treatment and interstitial treatment. In interstitial treatments, q-switched lasers are often coupled with optical fibers for use in surgery. Laser energy has also been used indirectly in treatments such as Photodynamic Therapy (PDT). In PDT, laser radiation is used to activate photo-reactive substances, which have been applied to a particular treatment zone.
There are many safety issues to be concerned with however, when using lasers in the place of conventional heat producing sources. With interstitial laser treatments such as ocular, vein treatment, hair removal, and other comparable treatments, there is less risk that the operator will be exposed to laser radiation. For many surface treatments however, many safety precautions must be taken to protect the operator and patient. State of the art systems often require cumbersome or expensive safety equipment. For example some laser systems include auto-locking doors for the operation room that cannot be opened from the outside while the laser source is running. These auto-locking doors prevent unprotected personnel from entering the treatment room. These safety requirements also mean that most laser equipment can only be used in a clinical setting. It would be advantageous if a system that fulfilled the safety requirements could be used in non-clinical settings.
U.S. Pat. No. 5,877,825 describes a type of protective eyewear for use with a pulsed laser radiation source. This protective device incorporates an electro optical shutter that causes the safety glasses' lens to become opaque during each pulse of radiation. The drawback to this invention is that every technician present must be tied into the protective system. Furthermore, this invention does not protect anyone who enters the treatment room by accident.
Many laser safety systems employ state of the art in situ visualization methods such as CCD cameras, image viewing, and processing units. This method eliminates an operator's exposure to laser radiation. Many surgeons and technicians however, prefer to operate using their own eyesight.
It is therefore the goal of the present invention to provide a method to protect medical personnel from exposure to laser radiation. The current invention will allow surgeons and technicians to use their own sight to perform operations, while still meeting safety requirements. The limitations of the prior art are overcome by the utilizing the current invention system.